Though ideal for picnics, you'll think of any excuse to make this rich, savory pie, especially when zucchini is in season. To punch up the flavor, add a small handful of chopped fresh herbs or a generous pinch of freshly grated nutmeg.
Preheat the oven to 350 degrees.
Slice 1 zucchini very thinly and set aside. Grate the remaining zucchini, firmly squeezing them by the handful to remove as much liquid as possible.
In a large bowl, whisk together the flour and eggs. Reserve ½ cup of the cheese, and then stir the grated zucchini and remaining cheese into the egg mixture.
Transfer to the pie crust, top with the sliced zucchini (arranging it in circles, if you like) and reserved cheese, and bake until firm and golden brown, 50-55 minutes. Set aside to let cool, and then serve warm or cold.